Study of natural inducer for coral larval settlement and metamorphosis.

从硬壳珊瑚藻（Hydrolithon reinboldii）中分离到一种新的促进蜕变的大内酯——发光内酯（luminaolide）。通过光谱分析确定了其结构。经ODS凝胶柱层析，经80%水溶液MeOH洗脱后得到1.30 μg/mL的提取物，对紫花赤霉的诱导活性为25.9±7.4%，添加1 （25.6 ng/mL）后，其诱导活性进一步增强至92.6±2.9%。制备了包括11-deoxyfistularine-3在内的8种溴酪氨酸衍生物，并测试了它们对硬核珊瑚Pseudosiderastrea tayamai幼虫的变态诱导活性。注意到以下构效关系：(i)两个螺旋异恶唑啉部分是必需的，两个螺旋异恶唑啉部分之间的酪胺衍生物对活性不是必需的。（ii）每个螺异恶唑啉部分的两个羟基对活性很重要。

A new metamorphosis-enhancing macrodiolide, luminaolide, was isolated from the crustose coralline algae (CCA) Hydrolithon reinboldii. Its structure was determined by spectroscopic analysis. A fraction (1.30 μg/mL) eluted with 80% aqueous MeOH by ODS gel column chromatography of the same CCA extract induced larval metamorphosis (25.9±7.4%) against Leptastrea purpurea, and its metamorphosis-inducing activity was further enhanced to 92.6±2.9% with the addition of 1 (25.6 ng/mL).Furthermore, eight bromotyrosine derivatives including 11-deoxyfistularine-3 were prepared and tested for their metamorphosis-inducing activity against larvae of scleractinian coral Pseudosiderastrea tayamai. The following structure-activity relationships were noted : (i) two spiroisoxazolin moieties are essential, tyramine derivetive between both spiroisoxazolin moieties is not essential for the activity. (ii) Two hydroxyl groups in each spiroisoxazolin moiety are important for the activity.